Investigating the carbon cycle in the world's oceans
Nearly all of the world's carbon is stored in the deep parts of the world's oceans. As levels of carbon dioxide in the atmosphere continue to rise at an alarming rate, so do concerns about the ocean's ability to deal with this increasing load. The Energy, Environment and Sustainable Development Programme funded the ORFOIS project consortium, eight partners in total, to provide some insight. CEA, a French research organisation, undertook the task of extending current knowledge regarding carbonate dissolution kinetics. The depth and vastness of the world's oceans makes them a difficult place to conduct research, so CEA recreated the ocean in their laboratory. Analysis of solubility products was conducted on samples gathered from two bathymetric transects in the eastern Atlantic Ocean in artificial seawater in the laboratory. The solubility product varies greatly depending on temperature, pressure and the size and composition of the biogenic marine carbonate. The solubility products calculated for calcite and aragonite were consistent with previous research but could not explain the changes in the carbonate fraction with depth observed in the eastern Atlantic. Dissolution kinetics were also investigated. The data revealed asymptotic concentration products, with the ratio of calcite to aragonite dissolution increasing with depth. CEA and its ORFOIS partners are making their findings available to the research community through a number of scientific publications.
